December 23 (SeeNews) - The main share indices of the Zagreb Stock Exchange (ZSE) ended mixed on Thursday, the last trading day before Christmas, amid gains in ICT solutions provider Ericsson Nikola Tesla [ZSE:ERNT] and OT-Optima Telekom [ZSE:OPTE], and losses in Hrvatski Telecom [ZSE:HT] and hotel operator Valamar [ZSE:RIVP], bourse data showed.